Reptilia M-LOK Handguard for AR-15/M4
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits all M4 upper receivers on AR-15 and M4 rifles. Barrel nut torqued to 50 ft-lb; turnbuckle set hand tight with red thread locker. Barrel Nut and Turnbuckle Wrench sold separately. Lengths 10.5 in, 13 in and 15 in, in Black Anodized and FDE Anodized.
Not sure it fits your rifle? Ask us before you order
The Reptilia Handguard is a free-float M-LOK handguard for AR-15 and M4 rifles, clamping to the barrel nut with Reptilia's patented turnbuckle system.
A turnbuckle clamp instead of a row of pinch screws — the handguard pulls itself square to the receiver.
Most free-float handguards are located by a ring of screws squeezing a split collar, and getting one to sit truly square and stay there is a job in itself. Reptilia's patented turn buckle technology takes a different route: the barrel nut goes on to a 50 ft-lb torque spec, then the turnbuckle is brought up hand tight with red thread locker and draws the handguard into alignment against it.
The tube itself is a 6061-T6 aluminium extrusion with a 33.5 mm internal diameter, finished in MIL-STD Type III, Class 2 hard anodise, and M-LOK slotted for accessories. Three lengths are offered here — 10.5 in at 255 g, 13 in at 309 g and 15 in at 358 g — each in Black Anodized or FDE Anodized.
Fits all M4 upper receivers, on AR-15 and M4 rifles. The supplied barrel nut is torqued to 50 ft-lb and the turnbuckle is set hand tight with red thread locker, so fitting is normal armourer's work with the usual AR tooling. Reptilia's Barrel Nut and Turnbuckle Wrench is the recommended tool and is sold separately. M-LOK accessories such as the SOCKET QD Sling Mount and the Low Profile M-LOK Rail mount directly to it.
| Platform | AR-15 / M4 |
|---|---|
| Fits | All M4 upper receivers |
| Type | Free-float M-LOK handguard |
| Material | 6061-T6 aluminium extrusion |
| Finish | MIL-STD Type III, Class 2 hard anodised — Black Anodized, FDE Anodized |
| Weight | 10.5 in 255 g (9.0 oz) · 13 in 309 g (10.9 oz) · 15 in 358 g (12.6 oz) |
| Length | 10.5 in, 13 in, 15 in |
| Mount interface | M-LOK; 33.5 mm internal diameter; barrel nut torqued to 50 ft-lb |
| Made in | USA |
| Brand | Reptilia |
| MPN | 100-356 · 100-357 · 100-359 · 100-337 · 100-339 · 100-340 |
A free-float tube that solves alignment mechanically rather than by feel. Order the Reptilia Handguard today — imported from the USA with all duties paid by us and dispatched tracked from the UK in 7–10 business days, with nothing to pay on delivery.
Explore more: M-LOK Accessories, AR-15 Parts or browse all Reptilia.
| Platform | AR-15 / M4 |
|---|---|
| Fits | All M4 upper receivers |
| Type | Free-float M-LOK handguard |
| Material | 6061-T6 aluminium extrusion |
| Finish | MIL-STD Type III, Class 2 hard anodised — Black Anodized, FDE Anodized |
| Weight | 10.5 in 255 g (9.0 oz) · 13 in 309 g (10.9 oz) · 15 in 358 g (12.6 oz) |
| Length | 10.5 in, 13 in, 15 in |
| Mount interface | M-LOK; 33.5 mm internal diameter; barrel nut torqued to 50 ft-lb |
| Made in | USA |
| Brand | Reptilia |
| MPN | 100-356 · 100-357 · 100-359 · 100-337 · 100-339 · 100-340 |
| Category | Handguard |
| Barcode | 850053448980 |
£5 tracked UK delivery on every order via Royal Mail Tracked 24. Our products are ordered in from the manufacturer rather than held in UK stock, so please allow 7 to 10 business days (Monday to Friday, excluding bank holidays) from the date of your order for it to reach you. Tracking details are emailed on dispatch. UK delivery only.
You have 30 days from receiving your order to cancel it for any reason, then 14 days to send it back unused and in its original packaging. Faulty, damaged or incorrect items are replaced or refunded and we cover reasonable return postage. Refunds go back to your original payment method within 14 days of receiving the return.
The barrel nut is fitted and torqued to 50 ft-lb, then Reptilia's patented turnbuckle is brought up hand tight against it with red thread locker. That draws the handguard into alignment with the receiver rather than relying on a ring of pinch screws to hold it square.
Reptilia's Barrel Nut and Turnbuckle Wrench is the recommended tool and is sold separately — it is not supplied with the handguard. The rest of the job uses normal AR armourer's tooling.
10.5 in, 13 in and 15 in are offered here. Length is governed by your barrel and gas system — the handguard needs to clear the gas block and end where you want the support hand to work. If you are unsure, tell us your barrel length and gas system and we will help.
They are priced as our supplier lists them, and on the 10.5 in and 13 in lengths the two finishes carry different prices. Nothing else differs between them — same tube, same material, same finish specification.
Handguards are sent from the United Kingdom with £5 tracked UK delivery in 7–10 business days, with tracking by email when it ships. If it is the wrong fit, <a href="/pages/contact">contact us</a>.
7 to 10 business days from the date of your order. Every order is sent Royal Mail Tracked for a flat £5 and you receive tracking details by email when it is dispatched.
Yes. We list only genuine parts and optics from the brands shown, ordered in from the manufacturer for your order.
Compatibility notes on this page come from the manufacturer. If you are unsure, email us with your make and model before ordering and we will check rather than guess.
Yes. Bundle & Save applies automatically in your basket: 5% off when you buy 2 items, 10% off at 3 items and 15% off at 4 or more. It works across the whole range, so you can mix and match, and there is no code to enter.
Yes — you have 30 days from delivery to cancel for any reason, as long as the item is unused and in its original packaging. See our returns policy for the details.
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